2001 Ford F-350 dies when I move the vent control

While rotating the vent control past the “off” position randomly the Powerstroke diesel engine may die if idling or momentarily spudder while driving. And less often randomly otherwise while the engine is running / driving the same may affect of dying/ spuddering has happened without any switches being toutched. Thus far it has always restarted & runs fine. This has been happening since I acquired this pickup 5+ years & some 40K miles ago. This is an industrial work / service truck of which lives & some day will die in dusty & greasy surroundings. I’m convinced it is some kind computer glitch or faulty grounding. But I fear I have to wait until this becomes sever enough to not allow the engine to run.

It may be the HVAC flaps and doors are controlled by engine vacuum, and there is a large leak (loose hose, for example) that the engine control system is not able to compensate for.

I like your’ way of thinking but this turbo diesel has a belt driven vacuum pump to operate such items as vents and power brake booster due to the fact the intake manifold is not under consistent vacuum and once the turbo is spooled up is actually receiving positive intake air pressure. And furthermore even if this was not true the intake of a diesel has nothing to do with air / fuel ratio like a gasoline engine so any extra air allowed in only adds to the power and wouldn’t hinder the engine from running other than if the air is unfiltered and allowing debris in of which will eventually harm the engine.
Nice try, what ells can you think of that may be my trouble?

I know little about diesels. Anyone out there? Anyone know of a diesel-specific site to help?

how is your belt driven vacuum pump?
I can’t imagine just moving a vent door would put enough extra strain on the pump to make the engine bog down, but it’s a Ford. Not much would surprise me.

It’s defiantly an electrical issue I’m certain

Gotta be defiant if not solved in over a month.

A month, it’s been five years or so.

June 14, June 15 were the first posts. I think that means year 2018.

As long as the engine is getting a steady fuel supply under the correct pressure a diesel engine should run. Unlikely that the vent control would affect the diesel injector pump, so I’d guess changing the vent control is somehow affecting the electrical power to the fuel pump in the tank. Hook up a volt meter to that point as close to the pump as you can get, using the same ground the pump uses, and see if the symptom coincides with a drop in voltage at the fuel pump. About the only other two things I can think of, either the AC compressor or alternator is bogging down the engine for some reason, related to the vent control.

If you read the original post, it says this:

OP, I think the vent control may be a red herring. You also said this-

Unfortunately, these kind of intermittent failures can be very hard to track down as you’re well aware. The only other thing I would suggest is to look for others that may have experienced similar issues. A vehicle specific site might be a better venue for your situation.

Only other thought is the vacuum pump is involved. Likely, there are other things running off that pump and the system isn’t likely air tight so it may run periodically just to keep the vacuum up. Look at what else is connected to vacuum and try to get one or more working simultaneously to see if the pump running is causing the problem. Maybe it is mechanically failing and presenting a huge drag at times…

TwinTurbo, you are right - I hadn’t closely read the history of the problem in the original post.

No biggie. I wish I could say it never happened to me :wink:

a 2001 Powerstroke that randomly dies?

Have you tried replacing the Camshaft Position Sensor? These sensors are notorious for going out and not tripping a fault code.
1876736C91 is the International Harvester part number, I think. They are pretty easy to replace, but can be around $150. When one of my engines of that era/make start having stalling issues- that is about the first place I start.

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